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1.
Cereb Cortex ; 31(4): 2220-2237, 2021 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-33251540

RESUMEN

In normal old (Nold) and Alzheimer's disease (AD) persons, a high cognitive reserve (CR) makes them more resistant and resilient to brain neuropathology and neurodegeneration. Here, we tested whether these effects may affect neurophysiological oscillatory mechanisms generating dominant resting state electroencephalographic (rsEEG) alpha rhythms in Nold and patients with mild cognitive impairment (MCI) due to AD (ADMCI). Data in 60 Nold and 70 ADMCI participants, stratified in higher (Edu+) and lower (Edu-) educational attainment subgroups, were available in an Italian-Turkish archive. The subgroups were matched for age, gender, and education. RsEEG cortical sources were estimated by eLORETA freeware. As compared to the Nold-Edu- subgroup, the Nold-Edu+ subgroup showed greater alpha source activations topographically widespread. On the contrary, in relation to the ADMCI-Edu- subgroup, the ADMCI-Edu+ subgroup displayed lower alpha source activations topographically widespread. Furthermore, the 2 ADMCI subgroups had matched cerebrospinal AD diagnostic biomarkers, brain gray-white matter measures, and neuropsychological scores. The current findings suggest that a high CR may be related to changes in rsEEG alpha rhythms in Nold and ADMCI persons. These changes may underlie neuroprotective effects in Nold seniors and subtend functional compensatory mechanisms unrelated to brain structure alterations in ADMCI patients.


Asunto(s)
Ritmo alfa/fisiología , Enfermedad de Alzheimer/fisiopatología , Amnesia/fisiopatología , Corteza Cerebral/fisiopatología , Disfunción Cognitiva/fisiopatología , Escolaridad , Anciano , Enfermedad de Alzheimer/psicología , Amnesia/psicología , Disfunción Cognitiva/psicología , Electroencefalografía/métodos , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas , Descanso/fisiología , Descanso/psicología
2.
Alzheimer Dis Assoc Disord ; 33(3): 212-219, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31335454

RESUMEN

AIMS: The aims of this study were to assess vascular dysfunction in patients with Alzheimer disease (AD) by investigating cerebral vasomotor reactivity using transcranial Doppler ultrasound (TCD) and to evaluate any correlations between cerebral vasoreactivity and endothelium dysfunction. Moreover, the frequency of circulating progenitor cells (CPCs) and the blood concentration of vascular/inflammatory markers were evaluated. MATERIALS AND METHODS: We recruited 35 AD subjects and 17 age-matched, sex-matched, and education-matched healthy control subjects. Cerebral vasomotor reactivity was assessed by means of the TCD-based breath-holding index test (BHI). The level of CPCs was evaluated by means of flow cytometry from venous blood samples, while blood vascular/inflammatory markers were measured by means of enzyme-linked immunosorbent assay. RESULTS: Both cerebral assay blood flow velocity in the middle cerebral artery (MCAFV) and BHI values were significantly lower in AD subjects than in healthy controls (P<0.05). A positive trend was found between MCAFV and BHI values and Mini-Mental State Evaluation (MMSE) scores. Moreover, the hematopoietic progenitor cells' count was found to be lower in patients with AD than in controls (P<0.05). Finally, a significantly higher expression of the plasma chemokine CCL-2 was observed in AD patients than in healthy controls. CONCLUSIONS: Our results confirm that cerebral hemodynamic deterioration may be a critical marker of cognitive decline. Further studies are needed to investigate the role of circulating CPCs and chemokines as potential contributors to neurovascular dysfunction.


Asunto(s)
Enfermedad de Alzheimer , Biomarcadores/sangre , Arteria Cerebral Media , Ultrasonografía Doppler Transcraneal , Anciano , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/fisiopatología , Contencion de la Respiración , Circulación Cerebrovascular , Quimiocina CCL2/sangre , Femenino , Humanos , Masculino , Pruebas de Estado Mental y Demencia , Arteria Cerebral Media/diagnóstico por imagen , Arteria Cerebral Media/fisiopatología , Células Madre/inmunología
3.
Neurol Sci ; 38(6): 999-1007, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28283760

RESUMEN

Complementary alternative medicine, such as shiatsu, can represent a suitable treatment for primary headaches. However, evidence-based data about the effect of combining shiatsu and pharmacological treatments are still not available. Therefore, we tested the efficacy and safety of combining shiatsu and amitriptyline to treat refractory primary headaches in a single-blind, randomized, pilot study. Subjects with a diagnosis of primary headache and who experienced lack of response to ≥2 different prophylactic drugs were randomized in a 1:1:1 ratio to receive shiatsu plus amitriptyline, shiatsu alone, or amitriptyline alone for 3 months. Primary endpoint was the proportion of patients experiencing ≥50%-reduction in headache days. Secondary endpoints were days with headache per month, visual analogue scale, and number of pain killers taken per month. After randomization, 37 subjects were allocated to shiatsu plus amitriptyline (n = 11), shiatsu alone (n = 13), and amitriptyline alone (n = 13). Randomization ensured well-balanced demographic and clinical characteristics at baseline. Although all the three groups improved in terms of headache frequency, visual analogue scale score, and number of pain killers (p < 0.05), there was no between-group difference in primary endpoint (p = ns). Shiatsu (alone or in combination) was superior to amitriptyline in reducing the number of pain killers taken per month (p < 0.05). Seven (19%) subjects reported adverse events, all attributable to amitriptyline, while no side effects were related with shiatsu treatment. Shiatsu is a safe and potentially useful alternative approach for refractory headache. However, there is no evidence of an additive or synergistic effect of combining shiatsu and amitriptyline. These findings are only preliminary and should be interpreted cautiously due to the small sample size of the population included in our study. Trial registration 81/2010 (Ethical Committee, S. Andrea Hospital, Sapienza University, Rome, Italy).


Asunto(s)
Acupresión , Amitriptilina/uso terapéutico , Analgésicos no Narcóticos/uso terapéutico , Cefaleas Primarias/terapia , Adolescente , Adulto , Amitriptilina/efectos adversos , Analgésicos no Narcóticos/efectos adversos , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Proyectos Piloto , Método Simple Ciego , Resultado del Tratamiento , Adulto Joven
4.
Neurol Sci ; 38(1): 101-107, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27655157

RESUMEN

Although a large number of studies have examined possible differences in cognitive performance between Alzheimer's disease (AD) and vascular dementia (VaD), the data in the literature are conflicting. The aims of this study were to analyze the neuropsychological pattern of subjects affected by degenerative dementia without evidence of small vessel pathology (DD) and small vessel VaD subjects in the early stages and to investigate differences in the progression of cognitive impairment. Seventy-five patients with probable VaD and 75 patients with probable DD were included. All the subjects underwent a standard neuropsychological evaluation, including the following test: Visual Search, Attentional matrices, Story Recall, Raven's Coloured Progressive Matrices, Phonological and Semantic Verbal Fluency, Token, and Copying Drawings. The severity of cognitive impairment was stratified according to the MMSE score. Fifteen subjects with probable DD and 10 subjects with probable VaD underwent a 12-month cognitive re-evaluation. No significant difference was found between DD and VaD subjects in any of the neuropsychological tests except Story Recall in the mild cognitive impairment (P < 0.001). The re-test value was significantly worse than the baseline value in the MMSE (P = 0.037), Corsi (P = 0.041), Story Recall (P = 0.032), Phonological Verbal Fluency (P = 0.02), and Copying Drawings (P = 0.043) in DD patients and in the Visual Search test (P = 0.036) in VaD subjects. These results suggest that a neuropsychological evaluation might help to differentiate degenerative dementia without evidence of small vessel pathology from small vessel VaD in the early stages of these diseases.


Asunto(s)
Cognición/fisiología , Demencia Vascular/psicología , Demencia/psicología , Enfermedades Neurodegenerativas/psicología , Anciano , Anciano de 80 o más Años , Demencia/patología , Demencia Vascular/patología , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Enfermedades Neurodegenerativas/patología , Pruebas Neuropsicológicas
5.
Neurol Sci ; 36(6): 1033-4, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25739944

RESUMEN

We report a case of neurosyphilis presenting with meningitis and subacute multicranial neuropathy in a young immune-competent man. Signs of primary and secondary stages of syphilitic infection occurred almost contemporarily in our patient. MRI revealed the involvement of several cranial nerves. CSF examination proved to be diagnostic. Syphilitic meningitis should be considered among the differential diagnoses of subacute, multicranial neuropathy, or skull base meningitis. The clinical course of this patient shows that early diagnosis and treatment warrant a good neurological outcome.


Asunto(s)
Nervios Craneales/patología , Neurosífilis/diagnóstico , Polineuropatías/diagnóstico , Adulto , Diagnóstico Diferencial , Humanos , Masculino , Neurosífilis/líquido cefalorraquídeo
6.
Stroke ; 45(10): 2959-66, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25184356

RESUMEN

BACKGROUND AND PURPOSE: Cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), a rare autosomal dominant disorder caused by NOTCH3 mutations, is characterized by vascular smooth muscle and endothelial cells abnormalities, altered vasoreactivity, and recurrent lacunar infarcts. Vasomotor function may represent a key factor for disease progression. Tetrahydrobiopterin, essential cofactor for nitric oxide synthesis in endothelial cells, ameliorates endothelial function. We assessed whether supplementation with sapropterin, a synthetic tetrahydrobiopterin analog, improves endothelium-dependent vasodilation in CADASIL patients. METHODS: In a 24-month, multicenter randomized, double-blind, placebo-controlled trial, CADASIL patients aged 30 to 65 years were randomly assigned to receive placebo or sapropterin 200 to 400 mg BID. The primary end point was change in the reactive hyperemia index by peripheral arterial tonometry at 24 months. We also assessed the safety and tolerability of sapropterin. Analysis was done by intention-to-treat. RESULTS: The intention-to-treat population included 61 patients. We found no significant difference between sapropterin (n=32) and placebo (n=29) in the primary end point (mean difference in reactive hyperemia index by peripheral arterial tonometry changes 0.19 [95% confidence interval, -0.18, 0.56]). Reactive hyperemia index by peripheral arterial tonometry increased after 24 months in 37% of patients on sapropterin and in 28% on placebo; however, after adjustment for age, sex, and clinical characteristics, improvement was not associated with treatment arm. The proportion of patients with adverse events was similar on sapropterin and on placebo (50% versus 48.3%); serious adverse events occurred in 6.3% versus 13.8%, respectively. CONCLUSIONS: Sapropterin was safe and well-tolerated at the average dose of 5 mg/kg/day, but did not affect endothelium-dependent vasodilation in CADASIL patients. CLINICAL TRIAL REGISTRATION URL: https://www.clinicaltrialsregister.eu. Unique identifier: 2007-004370-55.


Asunto(s)
Biopterinas/análogos & derivados , CADASIL/tratamiento farmacológico , Endotelio Vascular/efectos de los fármacos , Vasodilatación/efectos de los fármacos , Adulto , Anciano , Biopterinas/farmacología , Método Doble Ciego , Femenino , Humanos , Hiperemia/tratamiento farmacológico , Masculino , Persona de Mediana Edad
7.
J Neuropsychiatry Clin Neurosci ; 25(4): 255-63, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24247852

RESUMEN

The role of interleukin-6 (IL-6) as a risk factor for developing depressive symptoms, neuropsychological impairment, and related functional and neurological symptom severity during the acute phase of ischemic stroke is still underexplored. Here, the authors assessed this issue, in 48 patients without significant clinical history for major medical illnesses or other factors that promote inflammation, 72 hours after a first-ever acute ischemic stroke. In the acute phase of ischemic stroke, increased IL-6 plays a key role in the onset of depressive disorders, apathy/amotivation, somatic symptoms of depression, and neurological/functional symptoms, resulting in higher disability and poor outcome of stroke patients.


Asunto(s)
Depresión/complicaciones , Interleucina-6/sangre , Accidente Cerebrovascular/sangre , Accidente Cerebrovascular/psicología , Evaluación de Síntomas , Anciano , Biomarcadores/sangre , Isquemia Encefálica/sangre , Isquemia Encefálica/complicaciones , Isquemia Encefálica/psicología , Depresión/sangre , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas , Escalas de Valoración Psiquiátrica , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/complicaciones
8.
Arch Ital Biol ; 151(4): 169-78, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24873925

RESUMEN

Cognitive alterations accompany or follow motor disorders in subjects with Parkinsonism. The canonical phenotypeof the Parkinson's disease Dementia (PD-D) or Lewy Body Dementia (LBD) includes deficit of attention, executiveand visuospatial functions, and presents often with apathy, hallucinations, delusions, excessive daytime sleepiness,or sleep disorders. However, the clinical expression may overlap with other neurodegenerative diseases associatedwith cognitive disorders. Thus, while clinicians rely on phenomenological patterns to infer the disease causing thecognitive impairment, the inference is weakened by the heterogeneous clinical expression of the disease. In addition,recent post-mortem studies seem to undermine the supposed pathology-phenotype coherence, making it moreand more unreliable the diagnosis based on symptoms. The lack of coherence between phenotype and pathologymay support the speculation about a common mechanism underlying the progression of the disease. While it is verylikely that a distinct, specific causal event determines the disease itself, the progression might well follow commonpatterns. A number of observations suggest that progressive diseases, which cause cognitive impairment, share aprion-like mechanism. A seeding process is supposed to account for the spreading of the lesion.

9.
Eur Neurol ; 67(1): 34-8, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22156760

RESUMEN

BACKGROUND: Transient ischemic attacks (TIAs) bear a presumed high risk of early recurrence of stroke. Data in the literature, however, are inconsistent, as recurrence rates range from 9.5 to 20%, at 90 days. AIMS: The study was designed to determine the risk of stroke after TIA. METHODS: 94 consecutive patients referred to a Stroke Unit for TIA or minor stroke, within 24 h of symptom onset, were recruited. Eleven of the 94 patients (12%, 95% CI: 7-20%) had a relapse within 90 days. The relapse consisted of a TIA for 9 patients (10%, 95% CI: 5-17%), or of a stroke for 2 subjects (1%, 95% CI: 0-8%). More than a quarter of the relapses occurred within 1 week from the first TIA. ABCD(2), ABCD(2)-I and ABCD-E+ scores were similar among people with or without relapse. CONCLUSIONS: The data seem to confirm previous reports on the relatively low relapse rate for stroke, when TIA patients are promptly assisted in dedicated structures. The findings stress the potential benefit of early intervention in subjects with TIA.


Asunto(s)
Ataque Isquémico Transitorio/diagnóstico , Accidente Cerebrovascular/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Recurrencia , Riesgo , Medición de Riesgo
10.
J Headache Pain ; 13(3): 231-8, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22302157

RESUMEN

CADASIL is a hereditary disease characterized by cerebral subcortical microangiopathy leading to early onset cerebral strokes and progressive severe cognitive impairment. Until now, only few studies have investigated the extent and localization of grey matter (GM) involvement. The purpose of our study was to evaluate GM volume alterations in CADASIL patients compared to healthy subjects. We also looked for correlations between global and regional white matter (WM) lesion load and GM volume alterations. 14 genetically proved CADASIL patients and 12 healthy subjects were enrolled in our study. Brain MRI (1.5 T) was acquired in all subjects. Optimized-voxel based morphometry method was applied for the comparison of brain volumes between CADASIL patients and controls. Global and lobar WM lesion loads were calculated for each patient and used as covariate-of-interest for regression analyses with SPM-8. Compared to controls, patients showed GM volume reductions in bilateral temporal lobes (p < 0.05; FDR-corrected). Regression analysis in the patient group revealed a correlation between total WM lesion load and temporal GM atrophy (p < 0.05; uncorrected), not between temporal lesion load and GM atrophy. Temporal GM volume reduction was demonstrated in CADASIL patients compared to controls; it was related to WM lesion load involving the whole brain but not to lobar and, specifically, temporal WM lesion load. Complex interactions between sub-cortical and cortical damage should be hypothesized.


Asunto(s)
CADASIL/patología , Sustancia Gris/patología , Adulto , Atrofia/patología , Estudios de Casos y Controles , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Análisis de Regresión , Lóbulo Temporal/patología
11.
Mult Scler ; 17(10): 1155-61, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21613334

RESUMEN

The delayed conditioned eyeblink reflex, in which an individual learns to close the eyelid in response to a conditioned stimulus (e.g. a tone) relies entirely on the functional integrity of a cerebellar motor circuitry that involves the contingent activation of Purkinje cells by parallel and climbing fibres. Molecular changes that disrupt the function of this circuitry, in particular a loss of type-1 metabotropic glutamate receptors (mGlu1 receptors), occur in Purkinje cells of patients with multiple sclerosis and in mice with experimental autoimmune encephalomyelitis as a result of neuroinflammation. mGlu1 receptors are required for cerebellar motor learning associated with the conditioned eyeblink reflex. We propose that the delayed paradigm of the eyeblink conditioning might be particularly valuable for the detection of subtle abnormalities of cerebellar motor learning that are clinically silent and are not associated with demyelinating lesions or axonal damage. In addition, the test might have predictive value following a clinically isolated syndrome, and might be helpful for the evaluation of the efficacy of drug treatment in multiple sclerosis.


Asunto(s)
Parpadeo/fisiología , Enfermedades Cerebelosas/fisiopatología , Condicionamiento Clásico/fisiología , Esclerosis Múltiple/diagnóstico , Animales , Enfermedades Cerebelosas/metabolismo , Diagnóstico Precoz , Humanos , Ratones , Esclerosis Múltiple/metabolismo , Esclerosis Múltiple/fisiopatología , Receptores de Glutamato Metabotrópico/metabolismo
12.
Neurol Sci ; 37(10): 1755-6, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27519036
13.
J Alzheimers Dis ; 82(3): 1085-1114, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34151788

RESUMEN

BACKGROUND: In relaxed adults, staying in quiet wakefulness at eyes closed is related to the so-called resting state electroencephalographic (rsEEG) rhythms, showing the highest amplitude in posterior areas at alpha frequencies (8-13 Hz). OBJECTIVE: Here we tested the hypothesis that age may affect rsEEG alpha (8-12 Hz) rhythms recorded in normal elderly (Nold) seniors and patients with mild cognitive impairment due to Alzheimer's disease (ADMCI). METHODS: Clinical and rsEEG datasets in 63 ADMCI and 60 Nold individuals (matched for demography, education, and gender) were taken from an international archive. The rsEEG rhythms were investigated at individual delta, theta, and alpha frequency bands, as well as fixed beta (14-30 Hz) and gamma (30-40 Hz) bands. Each group was stratified into three subgroups based on age ranges (i.e., tertiles). RESULTS: As compared to the younger Nold subgroups, the older one showed greater reductions in the rsEEG alpha rhythms with major topographical effects in posterior regions. On the contrary, in relation to the younger ADMCI subgroups, the older one displayed a lesser reduction in those rhythms. Notably, the ADMCI subgroups pointed to similar cerebrospinal fluid AD diagnostic biomarkers, gray and white matter brain lesions revealed by neuroimaging, and clinical and neuropsychological scores. CONCLUSION: The present results suggest that age may represent a deranging factor for dominant rsEEG alpha rhythms in Nold seniors, while rsEEG alpha rhythms in ADMCI patients may be more affected by the disease variants related to earlier versus later onset of the AD.


Asunto(s)
Envejecimiento/fisiología , Ritmo alfa/fisiología , Enfermedad de Alzheimer/diagnóstico por imagen , Amnesia/diagnóstico por imagen , Cognición/fisiología , Disfunción Cognitiva/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Envejecimiento/psicología , Enfermedad de Alzheimer/fisiopatología , Enfermedad de Alzheimer/psicología , Amnesia/fisiopatología , Amnesia/psicología , Disfunción Cognitiva/fisiopatología , Disfunción Cognitiva/psicología , Electroencefalografía/métodos , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Descanso/fisiología , Descanso/psicología
15.
Neurol Sci ; 31(1): 1-8, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19838624

RESUMEN

Recent studies suggest strong interactions between cerebrovascular and Alzheimer's disease (AD) pathology. These conditions share common risk factors and individuals having both frequently show greater cognitive impairment than those affected by only one disease. Many studies point to early vascular dysregulations in AD. The exchange between vascular and neural cells occurs through mechanisms not completely understood, involving interactions among endothelial, glial, neuronal and smooth muscle cells within the neurovascular unit. Studies suggest that the dysregulation of the unit is likely associated with hypertension and other systemic diseases. Associations between hypertension and cognitive decline are not established, but other variables associated with hypertension could create a causal link. Many studies have lacked a consistent, quantitative neuropsychological approach for assessing cognitive functions. This approach is reductive, as the need for a formal neuropsychological assessment has gained broad recognition, and the definition of dementia has gone through revision processes, which are in progress.


Asunto(s)
Enfermedad de Alzheimer/fisiopatología , Endotelio Vascular/fisiopatología , Encéfalo/irrigación sanguínea , Encéfalo/fisiopatología , Trastornos del Conocimiento/fisiopatología , Humanos , Hipertensión Intracraneal/fisiopatología
16.
J Clin Neurosci ; 73: 8-12, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31948882

RESUMEN

Despite the large body of data available, chronic cerebral hypoperfusion lacks an operative definition. In a tautological way, the term hypoperfusion is being referred to conditions of "inadequate blood flow", "defects of perfusion" or "dysfunction of autoregulation". The chronicity refers to sustained conditions or wavering states characterized by repeated phases of inefficient functional hyperemia. The phenomenon may affect the whole brain or defined areas. A few defined clinical disorders, including heart failure, hypotension, atherosclerosis of large or small vessels and carotid stenosis are thought to cause progressive brain disorders due to chronic hypoperfusion. The clinical relevance manifests mostly as neurocognitive disorders associated with neuroimaging changes.The available data support a conceptual framework that considerschronic cerebral hypoperfusiona likely, relevant pathogenic mechanism for the neurodegeneration-like progression of the neurocognitive disorders. The relationship between neuropathology, cerebral perfusion, and symptoms progression is, however, elusive for several aspects. Typical microangiopathy findings, such as MRI white matter hyperintensities, may appear in individuals without any cerebrovascular risk or vascular lesions. Pathology features of the MRI changes, such as demyelination and gliosis, may result from dysfunction of the neuro-vascular unit not directly associated withvascular mechanisms. In this review, we aim to overview the most common clinical conditions thought to reflect chronic hypoperfusion.


Asunto(s)
Encéfalo/irrigación sanguínea , Encéfalo/diagnóstico por imagen , Circulación Cerebrovascular/fisiología , Trastornos Neurocognitivos/diagnóstico por imagen , Trastornos Neurocognitivos/fisiopatología , Animales , Encéfalo/patología , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/fisiopatología , Enfermedad Crónica , Progresión de la Enfermedad , Homeostasis/fisiología , Humanos , Imagen por Resonancia Magnética/métodos
17.
Front Neuroanat ; 14: 17, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32372921

RESUMEN

Most neurological disorders seemingly have heterogenous pathogenesis, with overlapping contribution of neuronal, immune and vascular mechanisms of brain injury. The perivascular space in the brain represents a crossroad where those mechanisms interact, as well as a key anatomical component of the recently discovered glymphatic pathway, which is considered to play a crucial role in the clearance of brain waste linked to neurodegenerative diseases. The pathological interplay between neuronal, immune and vascular factors can create an environment that promotes self-perpetration of mechanisms of brain injury across different neurological diseases, including those that are primarily thought of as neurodegenerative, neuroinflammatory or cerebrovascular. Changes of the perivascular space can be monitored in humans in vivo using magnetic resonance imaging (MRI). In the context of glymphatic clearance, MRI-visible enlarged perivascular spaces (EPVS) are considered to reflect glymphatic stasis secondary to the perivascular accumulation of brain debris, although they may also represent an adaptive mechanism of the glymphatic system to clear them. EPVS are also established correlates of dementia and cerebral small vessel disease (SVD) and are considered to reflect brain inflammatory activity. In this review, we describe the "perivascular unit" as a key anatomical and functional substrate for the interaction between neuronal, immune and vascular mechanisms of brain injury, which are shared across different neurological diseases. We will describe the main anatomical, physiological and pathological features of the perivascular unit, highlight potential substrates for the interplay between different noxae and summarize MRI studies of EPVS in cerebrovascular, neuroinflammatory and neurodegenerative disorders.

19.
Int J Psychophysiol ; 158: 259-270, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33080295

RESUMEN

Extending Basar's theory of event-related EEG oscillations, here we hypothesize that even in quiet wakefulness, transient increases in delta rhythms may enhance global cortical arousal as revealed by the desynchronization of alpha rhythms in normal (Nold) seniors with some derangement in Alzheimer's disease dementia (ADD). Clinical and EEG datasets in 100 ADD and 100 Nold individuals matched as demography, education, and gender were taken from an international archive. Standard delta (< 4 Hz) and alpha1 (8-10.5 Hz) bands were used for the main analysis, while alpha2 (10.5-13 Hz), theta (4-8 Hz), beta1 (13-20 Hz), beta2 (20-35 Hz), and gamma (35-40 Hz) served as controls. In the interpretation, the higher the alpha1 power (density), the lower that arousal. As expected, when compared to the Nold group, the ADD group showed higher global (scalp) power density at the delta-theta band and lower global power density at the alpha-beta bands. As novel findings, we observed that: (1) in the Nold group, the global delta and alpha1-2 power were negatively and linearly correlated; (2) in the ADD group, this correlation was just marginal; and (3) in both Nold and AD groups, the EEG epochs with the highest delta power (median value for stratification) were associated with the lowest global alpha1 power. This effect was related to eLORETA freeware solutions showing maximum alpha1 source activations in posterior cortical regions. These results suggest that even in quiet wakefulness, delta and alpha rhythms are related to each other, and ADD partially affects this cross-band neurophysiological mechanism.


Asunto(s)
Enfermedad de Alzheimer , Corteza Cerebral , Ritmo Delta , Electroencefalografía , Humanos , Descanso , Vigilia
20.
Clin Neurophysiol ; 131(11): 2716-2731, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33039748

RESUMEN

OBJECTIVE: Here we tested if cortical sources of resting state electroencephalographic (rsEEG) rhythms may differ in sub-groups of patients with prodromal and overt dementia with Lewy bodies (DLB) as a function of relevant clinical symptoms. METHODS: We extracted clinical, demographic and rsEEG datasets in matched DLB patients (N = 60) and control Alzheimer's disease (AD, N = 60) and healthy elderly (Nold, N = 60) seniors from our international database. The eLORETA freeware was used to estimate cortical rsEEG sources. RESULTS: As compared to the Nold group, the DLB and AD groups generally exhibited greater spatially distributed delta source activities (DLB > AD) and lower alpha source activities posteriorly (AD > DLB). As compared to the DLB "controls", the DLB patients with (1) rapid eye movement (REM) sleep behavior disorders showed lower central alpha source activities (p < 0.005); (2) greater cognitive deficits exhibited higher parietal and central theta source activities as well as higher central, parietal, and occipital alpha source activities (p < 0.01); (3) visual hallucinations pointed to greater parietal delta source activities (p < 0.005). CONCLUSIONS: Relevant clinical features were associated with abnormalities in spatial and frequency features of rsEEG source activities in DLB patients. SIGNIFICANCE: Those features may be used as neurophysiological surrogate endpoints of clinical symptoms in DLB patients in future cross-validation prospective studies.


Asunto(s)
Corteza Cerebral/fisiopatología , Disfunción Cognitiva/fisiopatología , Red en Modo Predeterminado/fisiopatología , Alucinaciones/fisiopatología , Enfermedad por Cuerpos de Lewy/fisiopatología , Anciano , Ritmo alfa/fisiología , Sincronización Cortical/fisiología , Electroencefalografía , Femenino , Humanos , Masculino , Síntomas Prodrómicos , Estudios Prospectivos
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